Dimpled marine seismic fairing

Abstract

An apparatus and method for improving the efficiency of marine cable tow operations. Indentations such as dimples in the exterior surface of cable fairings reduce cable strumming and reduce frictional drag forces as the cables and fairings are towed through the water. The size, configuration and orientation of the indentations can be selected to control the desired water flow parameters, and overall tow efficiency is increased.

What is claimed is:  
     
       1. An apparatus for reducing friction acting against a marine cable towable through water, comprising: 
       a fairing body engagable with the cable, wherein said body has an exterior surface in contact with the water; and  
       a plurality of indentations in said body exterior surface for reducing friction as said body is towed through the water.  
     
     
       2. An apparatus as recited in  claim 1 , wherein said indentations comprise dimples. 
     
     
       3. An apparatus as recited in  claim 1 , wherein said indentations are symmetrically configured. 
     
     
       4. An apparatus as recited in  claim 3 , wherein at least one of said indentations is configured in a round dish shape. 
     
     
       5. An apparatus as recited in  claim 3 , wherein at least one of said indentations is configured in a polygonal shape. 
     
     
       6. An apparatus as recited in  claim 3 , wherein at least two different shapes of indentations are formed in said body exterior surface. 
     
     
       7. An apparatus as recited in  claim 1 , wherein said indentations are oriented in a particular pattern on said body exterior surface. 
     
     
       8. An apparatus as recited in  claim 1 , wherein at least two of said indentations have different sizes. 
     
     
       9. An apparatus as recited in  claim 1 , further comprising a splitter plate attached to said body. 
     
     
       10. A fairing for reducing drag on a cable towable through water, comprising: 
       a body having an exterior surface in contact with the water, wherein said body has a lead end and a tapered second end; and  
       a plurality of indentations in said body exterior surface for reducing friction as said body is towed through the water.  
     
     
       11. An apparatus as recited in  claim 10 , wherein said indentations are symmetrically configured. 
     
     
       12. An apparatus as recited in  claim 10 , wherein at least two different shapes of indentations are formed in said body exterior surface. 
     
     
       13. An apparatus as recited in  claim 10 , wherein said indentations are oriented in a particular pattern on said body exterior surface. 
     
     
       14. An apparatus as recited in  claim 10 , wherein said cable comprises a marine seismic cable. 
     
     
       15. An apparatus as recited in  claim 10 , further comprising a splitter plate attached to said body. 
     
     
       16. A method for towing a cable in water, comprising the steps of: 
       attaching a fairing to the cable, wherein said fairing has an exterior surface having a plurality of indentation for reducing friction;  
       deploying a cable and attached fairing in the water behind a tow vessel; and  
       moving the tow vessel to tow said cable through the water.  
     
     
       17. A method as recited in  claim 16 , further comprising the step of deploying a fairing in the water wherein at least two of said indentations have different configurations. 
     
     
       18. A method as recited in  claim 16 , further comprising the step of deploying a fairing in the water wherein at least two of said indentations have different sizes. 
     
     
       19. A method as recited in  claim 16 , further comprising the steps of attaching a plurality of fairings to the cable. 
     
     
       20. A method as recited in  claim 16 , further comprising the step of connecting marine seismic equipment to said cable before said cable and fairing are deployed in the water.